Spray gun



Dec. 7,1926. 1,610,190

A. L. ANDERSON SPRAY GUN Filed dgt. 12, 1925 j y' liatentetl Dec, 7, y

Y AXEL-L. ANnERSoN, 0F Rook'ronn, IL'LIIIOIS,4 .esSIGnon rro PEERLESS PIIEUMATIG Y SYSTEMS, INC.,V0F CHICAGO, ILLINOIS, A'COBPORATIQN or ILLINOIS.

' "iippiickatibn me@ octobef'lz, 1925.l

-This4 invention Vrelates tof air brushes or spray guns Vas they are commonly known,

for atomizing and spraying with air-asthe transportingV and motive luidsuch mate`' rials as paints, `fillers, enamels, varnishes, r shellaos,rdyes, stains and a variety of otherv of slugs and large particles' of paint beingv discharged With the spray andruining the character of'wor'k performed.`

In thecarrying out of 4the":toregoiing.ob#`Vv ject-I haveprovid'ed aguide in thematerial or Vcolor nozzle Jfor the stem ofthe needle val'vewhich controls-theV discharge of material from the nozzle,` arranged to serve to with 4the'discharge orice of then'ozzlein,V V

keep vthe valveein true concentricrelation all operating positions v thereof:

il The inventionifs more fully enceismade tothe Vaocovmpanying drawingi Fig.'lisa side view otra spray gunp'a portionf'of the head Vof Whichiis'shownsin section to illustrate thel application V:ofzm'y improved needle valve `stem guide;

Fig.vv 2 isal front yvievvV Qtth'eneedle valve I l on an enlarged scale illustrating` how yitis kept centered with respect .to the fbore'of thecolor nozzle, the bore being represented by 53'; dotted circle; and

Fig. 3 is an enlarged'fragmentary view of l 'the outer end of they needle valve, a' portion "ot'Whic'h, is shovvnin section toillustrate more clearly the constructionthereof.

i IA

Spray guns-of the type to 'Which the 'pres-l f ent invent-1on1 particularly relates, usually comprise a'handle 4:5 a head portion `5 and Y a connecting intermediate'barrel-like por- Y tion 6. The material to be discharged,inan-4 Vatomi'z'ed 'condition is. delivered through a neck 7 VYfrom va suitablejhose connection and at a lconstant -pressurerjvff'lrhe transporting Y orv motive?vv iiuid, usually air,v is. .admitted through a'hose extending Lfroma' suitable',^r

source"V of' supply l and' connected at the threaded nipple 8Y eXtendin'gofI0 the rear'oi i' the @handle 4.@ trigger Q rstraddles the deseaba@ in p the' Yfollowing specificationv in `which freferf seriai'n'olersza may (of the gun; mais piv'oaa Vuname.fia y front of Vthe handle 4l. It is'arranged.toy Voperate a Vneedle valvel'in front thereof."

to controly lthe discharge ot material from a material delivery yor colorinozzle l1." VThe trigger Y. also has f connection- V With the; stem of van air' valve l2 onza-yoke 113. rlhejyok'e 13 encloses a-'coiled'compression spring norfA mally holding the Avalve'llO'in closedposition at the front thereof and: urging the air valve 12' also forwardly toits 'seatV Within thebodyofthe gun inthe handled. The

valvelO and'gair valve are usually such astoiinsure ythe Vdisch,argingy of air previous connections of thetrigger)y Withthe needle..V

to they openingffotthe needle valveflO. The l movement 2 of'y the' trigger is :suitably` limited 'j by an'adj'ustabley set vscrevvdisposed cbehind thesameV and, threadingly engaged l in the handle' 4'. The discharge' ofy airis regulated byfan-adjustable needlevalve .l5-arranged i to be locked ink adjustedposition byanut'16.l

Y yThe detailsthusard'escribedare entirely conventional and`noinvention' isclairnedY therein except as theycontribute in part to the carrying outoie the present yinvention as :will hereinafteriappear.' I

The colornozzle 1l. t befnotevd,has

'1 ai 'reduced threaded end '11T Vsecured. into. the l jmateri'al inlet Vpassage/V18,(in the head. It

hasfan oppositeV externally threaded-.part 19 terminating 5 inl a :conical j discharge :nozzle end. 20.5 `The nozzle ll v'has a'centralbore oir j passagell which communicates fat one end With the' material: inlet i "passage 18` and'- f at Vtheopposite.lend With akconical passage' 22 in. the nozzleendQOgtermnating in a die# s chargegoriice 23. y The .enlarged intermedif ate 'portion of the* nozzle is suitably liefIa-gfon nal' in form tof permit the application of a Wrenchintightening the nozzle in the head 5. "A main'alr discharge nozzle. 24e has a re,

vduced"cylindrical portion v25` internally threadedtoiscr'evvVF on the externally threaded portion 194 ot the'nozzle ll'and-has a'flanged outerfend 2.6,-tlie peripheryof which is suitloo ably fknurled forv Convenience iny tightening the nozzle i in' position. Thenozzle24' has'V v i gits cylindricalportion 25`providinga bear-VA Y` ing' :tora'llat spray nozzle`27 andv thel flanged :end 26;'ja1ns ^`against.thek r'endfot the nozzlerj .v 27 to'hold it;se'c* urely' in position against-the Y 'Z v'at,rv outer face'QS ol thefheadl j The nozzle"v 27providesvan annular air 'chamberfl29 about the ln gzzlers, 11 erariali2e The anemie-24 nas-:.1105

vonto. the. atomized material a plurality, four in the present, instance, of

equally spaced radial ports 30 connecting the chamber l29 With a chamber 31 surrounding the nozzle portion 20Y and terminating in an air vdischarge orifice 32 concentric With the orifice 23 and surrounding the sanne. The;

flat spray nozzlev 27 is shaped to provide a pair of opposed heads 33 providedWfithgpas-V sages 34 leading from the air chamber 29 in divergingrelation and term-inatingina pair of converging dischargeorices 35 adapted for delivering two supplemental jets of air c from the central orifice V23 for the'purpose of flattening the Vsprayinto a line-like'dei livery. Vranged to he rotated for thepurpos'e of Thenozzle 27 is customarily ar-V changingzthe. plane ofthe flat spray about the axis' ofthe compound nozzle structure,

that is, to produce afvertical or horizontal or any-intermediate angular spray delivery,

Air is conducted to the chamber 29 Athrough a. ductr36leadin'g rearwardlythrough the f barrel 6j past the valve 15to-thezhore ofthe 'air supply n'ipple 8. Ther'description` thus Y far? vvill'4 sufic'e to'showthat the opening of thek valve 12 produces. a main discharge of air from the orifice'32 and supplemental air from the orifices. 35. The.materialis dischargedfrom the central orifice 23 in reg-uc lated'amounts past the pointed end 37 of the needle valve 10 shaped to Vlit snugly in Y the conicalV passage V22fof the nozzle v11.V

Y .ging one Wall in the nozzle permitted a .p'ro.j

The character ofthe spray delivered dependson- .proper atomizing-7 that,` is, proper intermixing of air with finelydivided or segregated material,V In previ-ous devices; con- Y ysideralole trouble was, experienced .1n y thisy particular because of Ythe inability to maintain `the nozzle. in true` concentric Vrelation withzthe rdischarge oriiicezor, vvhatamounts to the` same thing, to the conical passage terminating in theorifice, ,The needle inhugportionately greater flow past theineedle at the opposite Wall: Asa' result'there couldfloe Y' 1 no uniformity in the VsprayprodugcedA and f p necks-'and blotches'were formed'in-the surface being coated! or finished, becauseof large slugs ofthe raiv 'material being thrown onto' tlie Work Withoutk proper atomization.

Z The difculty referred to `vvaszfound toibe 1 due to the fact thatthe slightest firregulari tiesY-in production Would'throW the YneedleV out of line `With thenozzle when the Vparts tricity with the' nozzle at ltheoi'iter unsupported end of theneedle.A *As illustrated, thel stem of theneedle'valve 10`is reciprocablea i in a2V glandL nut 38 and' atY thisgpointconnection-is made -vvithi the trigger 9 on thecross head 39. The foregoingdiliiculties with re'- discharging I spectgto keeping the needle in alignment With the nozzle are avoided hy the provision of a spider` elemente() which, as appears in Fig. 2,V has three radial arms" of exactly equal length arrangedlto' center the :needle valve 10 with respect to the bore 21 'of the Vnozzle 11. Since the loorel 21Y is formed truly concentric,'Withthefconical passage 22fand discharge orifice 23 ofthe `nozzle 11, the pointed end 37 of thejneedleqvalveis kept properly centeredwith respect ,toV the afore-named passagef'and orifice. ln the operation of the'valve, the'f'spidergll-O slides 'in thehore 21 andV maintains thec'oncentric relation of the needle ivalve in,i all operationpositions thereu of.v B ueztotheffaet that; the hore,21is neces-V sarily scinewhat restricted, thel spider l0 is? preferably provided Without a hubportion toV t on; thestem of the needle` valve *i 10` as this World consttutefanf additional 'realiz-icT tieni. instead; it, hasta centralaopenngd throughs-. Which` the.: shank42 ofaepafeble needleftp 43iis1arranged-toa( The reduced shank 42 litswvitljiin a.; here lla'provided' in the outer end; ofthe stem-of thene'edlelvalve.

rlhe shank Al2jissuitably sweat-soldered, lorazed .orA OtherwiseA secured 1in the borev 44. The4 tip ishardenedA suita'h'lyfby immersion in molten cyanide;- Az small 'relief `1vent Ll5 isprovidedat the innerfendvofthjejlqere la to prevent the gtip, from beingzforced off, in :case

thereYhappenstoloer'some moisture? in the bore Y Whichgvvouldyhe vaporized-in the heatdotted i lined bore 46; may The; provided-,- if

Y ing of the tip'` inthe hardening processi, The Y desiredyfer furnishing the main .atomizila air:jetasrrlsclesecl ina @mandi-,ng applieafi tion of Swan F. Anderson, SerialNumber the guide v`vvh'ic'h jI. have just described, the

needlervalvewstem is-al'vvays kept concentric irregularities Whichfjmay occur in the pro-l duction ofthe vnozzljeltself or 1n the mounting of the needle valve inits guiding gland nutV 38. The removaloility Yof VVthe .nozzle `11Y and the'nozzles 2a and 27 will not operate,y

in cleaning` the gunorbv cominginto contoldestroy the alignment, inasmuchv as the spider 40 Yvvill always center the needle 4and ifi Y avoid Ythe disalignnient f that j sometimes oc` curred Where the needle .Was sprung ,slightlyV tact with somethingvvhen the nozzles Were Y not in place tov protect the needlevalve. Y

I claim: f

' l. In a spray gun'havinga material nozzle vand an air nozzle frming a compound spray nozzlexfor discharging-'material 1inV atomized y Vfor reception in a ,bore providedfin the' end;y of said stem portion, and a separate spider element arranged tobe concentric with Said l stem and tip having 4a central opening to receive the shank of said tip whereby to be assembled ,with said 'steinand tip between the same. Y 2. In a spray gun having a material nozzle and an air nozzle forming a compound spray nozzle for, discharging material in atomized Condition, a needle valve'structure orcontrolling the discharge from said materialiv nozzle comprising a stem portioma separate pointed 'tipportion having Va, reduced Shank for reception in. a bore provided in the end ofrsaid stern portion, anda separate spider element mounted on said .valve between the stem andV tipvportions and held in. placeby the connection thereof. l

3. In a spray gun having ainaterial nozzle and an air nozzle forming a compound spray nozzle for discharging material inatomized condition,a needle valve structure, for 'con-v trollingthe discharge from saidinaterial nozzle comprising Va stein portion, a separate pointedtip portion'having a reduced shank for'reception in a' bore provided in the end of said stem portion whereby to connect the two portions together, saidstem portion hav: Y Y

ing a relief vent at the inner end of thevbore mounted on said valve between the .stemand signature.

' i AXEL L.- ANDERSON. 

